# Chemistry

posted by Jamal

A mixture of 0.47 mole of H2 and 3.59 moles of HCl is heated to 2800C. Calculate the equilibrium partial pressures of H2 Cl2 and HCl if the total pressure is 2.00 atm. For the reaction Kp is 193 at 2800C.

H2(g) +Cl2(g) = 2HCl (g)

What I've done so far:

found the partial pressures of HCl and H2 by taking moles x / moles total = mole fraction x total pressure (2?)

Got:
1.77 atm for HCl
.233 atm for H2

Plugged into ICE chart but I'm not getting the right answer. These are supposedly the right answers:
HCl: 1.67 atm
H2: .282 atm
Cl2: .051

1. DrBob222

Your solution is not getting the right answers for two or three reasons.
a. You don't have a value for moles Cl2; therefore, you don't have total moles.
b. The moles given are at the start of the reaction (not at equilibrium) BUT total pressure of 2 atm is at equilibrium.
Here is how you approach the problem.
First, notice that you have two moles of products and two moles of reactants; therefore, Kp = Kc. Also note that you don't have a volume; however, moles/volume will give concn BUT the V term cancels in the Kc expression so we can ignore that (and I have ignored it below). You can assume some volume if it makes you feel any better but it cancels in the end, whatever you choose.

........H2 + Cl2 ==> 2HCl
I....0.47.....0.......3.59
C.....+x.....+x.......-2x
E.....0.47+x...x.......3.59-2x

Kp=Kc=(HCl)^2/(H2)(Cl2)
193 = (3.59-2x)^2/(0.47+x)(x)
solve for x.
Add moles to find total moles AT EQUILIBRIUM.
Then X*totalP will find partial pressures of each.
I worked the problem and the answers are correct.
Post your work if you get stuck.

2. Jamal

Got it. Thanks man.

## Similar Questions

1. ### Chemsitry II

mole fraction is equal to partial pressure divided by the total pressure Total pressure= sum of partial pressure use PV=nRT where n= number of moles equation become PV/RT=n make sure to convert the temperature to Kelvin and to use …
2. ### Chemistry

A mixture of 0.47 mole of H2 and 3.59 moles of HCl is heated to 2800C. Calculate the equilibrium partial pressures of H2 Cl2 and HCl if the total pressure is 2.00 atm. For the reaction Kp is 193 at 2800C. H2(g) +Cl2(g) = 2HCl (g) I …
3. ### CHEMISTRY

Equilibrium Equation with Partial Pressures PCl3(g) +Cl2(g) <-> PCl5(g)?
4. ### chemistry

SO2Cl2(g) SO2(g) + Cl2(g) The Kp for the reaction is 2.18 at 648 K. A sample of SO2Cl2 is placed in a container and heated to 648 K while the total pressure is kept constant at 9.00 atm. Calculate the partial pressures of the gases …
5. ### chemistry

at an equilibrium mixture of PCl5, PCl3, and Cl2 has partial pressures of 217.0 Torr, 13.2 Torr and 13.2 Torr respectively. a quantity of Cl2 is injected into the mixture, and the total pressure jumps to 263.0 Torr (at the moment of …
6. ### chemistry

at an equilibrium mixture of PCl5, PCl3, and Cl2 has partial pressures of 217.0 Torr, 13.2 Torr and 13.2 Torr respectively. a quantity of Cl2 is injected into the mixture, and the total pressure jumps to 263.0 Torr (at the moment of …
7. ### Chemistry***

A mixture containing 19.8 moles of H2 and 7.2 mole of I2 was allowed to reach equilibrium in a 5 L closed vessel at ToC according to the equation: H2 (g) + I2 (g) 2HI (g) At equilibrium, 14 moles of H2 was present. The equilibrium …
8. ### Chemistry

PCl5 is introduced into an evacuated chamber and comes to equilibrium (see Problem 16.37), at 250◦C and 2.00 atm. The equilibrium gas contains 40.7% Cl2 by volume. (a1) What are the partial pressures of the gaseous components …
9. ### Chemistry

Nitrogen monoxide reacts with chlorine gas according to the reaction: 2NO (g) + Cl2 (g) â‡” 2NOCl (g) Kp = 0.27 at 700 K A reaction mixture initially contains equal partial pressures of NO and Cl2 . At equilibrium, the partial …
10. ### chemistry

For 2SO2(g)+O2(g)⇌2SO3(g), Kp=3.0×104 at 700 K. In a 2.00-L vessel the equilibrium mixture contains 1.15 g of SO3 and 0.107 g of O2. 1) How many grams of SO2 are in the vessel?

More Similar Questions